Phonon is not really designed to handle multiple sounds at the same time. KALEngine is made for games and create one thread per sound, using the openAL library. You also get all the other openAL goodness like 3D sounds, effects and multichannel.

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==Installation==

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==Starting Point : the main.cpp==

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1: You need to have the following libraries installed.

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Every application needs one, so let's start with it, as it is really simple.

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* openAL (sound api)

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<code cppqt>

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* alut (openAL toolkit)

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</code cppqt>

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* libSndFile (load sound file).

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+

If you're using a Debian-based distribution, you can install them that way :

In this example, we will play a "Hello Word". We don't need to specify any sound file, openAL provides a default sound itself.

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<syntaxhighlight lang="cpp-qt">

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#include <KALEngine>

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#include <KALSource>

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#include <KDebug>

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int main(int argc, char **argv)

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{

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// create an OpenAL object

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KALEngine soundEngine;

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// initialize OpenAL context and device

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soundEngine.init();

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// create a sound, since we haven't specified any filename in the constructor, it will play the "Hello World"

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KALSource *sound = new KALSource();

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// play the sound

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sound->play();

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// print the elapsed time until the sound has finished playing

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while (sound->status() == AL_PLAYING)

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{

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kDebug() << sound->elapsedTime();

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}

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// clear the buffer

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delete sound;

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// ...and close the device

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soundEngine.shutdown();

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return 0;

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}

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</syntaxhighlight>

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- First, we initialize the sound engine. The init() function can optionally takes one argument, the device name. You can retrieve the list of devices, using this static function :

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<syntaxhighlight lang="cpp-qt">

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QStringList devicesList().

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</syntaxhighlight>

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- Then, we create a KALsource. KALSource can be used for playing small sounds(shoot, scream, tic, walk, etc). It will load the entire file inside a buffer, so be careful if you try to play a big file using it.

+

+

If you want to try playing something else than the default "Hello World", you can download this short simple : [[http://ktank.free.fr/kalengine/ocean.wav ocean.wav]] and replace the sound object definition by:

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<syntaxhighlight lang="cpp-qt">

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KALSource *sound = new KALSource("ocean.wav");

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</syntaxhighlight>

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You can only use it to play wav file at the moment, but we hope to bring ogg support soon.

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For playing music, please wait until KALStream tutorial is up.

+

+

- The sound can now be played by simply calling <b>play()</b>. This function is asynchronous, meaning your program doesn't have to wait until the sound has finished playing to continue.

+

+

- Then, to know when the sound has ended, we create a loop using <b>status()</b> which returns ever <b>AL_PLAYING</b> or <b>AL_STOPED</b>.

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- Inside the loop, we print the time since the sound started playing using <b>elapsedTime()</b>. It returns an ALfloat with the elapsed time expressed in seconds.

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- Finally, we have to clear the KALSource buffer by deleting the KALSource pointer and close the device by calling <b>shutdown()</b>.

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== Multi-channel ==

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sound1->play();

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sound2->play();

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...to develop

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== 3d sound ==

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KALSource->setPosition(x,y,z)

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...to develop

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{{tip|For more information on how OpenAL works, see the documentation [[http://connect.creativelabs.com/openal/Documentation/OpenAL_Programmers_Guide.pdf OpenAL programmers Guide ]]}}

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{{TODO|Create KALStream}}

Revision as of 08:36, 26 September 2011

KALEngine tutorial

Tutorial Series

KALEngine developement

Prerequisites

None

What's Next

Nothing at the moment

Further Reading

KGLEngine2d's code

Contents

Abstract

Phonon is not really designed to handle multiple sounds at the same time. KALEngine is made for games and create one thread per sound, using the openAL library. You also get all the other openAL goodness like 3D sounds, effects and multichannel.

Installation

1: You need to have the following libraries installed.

openAL (sound api)

alut (openAL toolkit)

libSndFile (load sound file).

If you're using a Debian-based distribution, you can install them that way :

Hello Word

In this example, we will play a "Hello Word". We don't need to specify any sound file, openAL provides a default sound itself.

#include <KALEngine>#include <KALSource>#include <KDebug>int main(int argc,char**argv){// create an OpenAL object
KALEngine soundEngine;// initialize OpenAL context and device
soundEngine.init();// create a sound, since we haven't specified any filename in the constructor, it will play the "Hello World"
KALSource *sound =new KALSource();// play the sound
sound->play();// print the elapsed time until the sound has finished playingwhile(sound->status()== AL_PLAYING){kDebug()<< sound->elapsedTime();}// clear the bufferdelete sound;// ...and close the device
soundEngine.shutdown();return0;}

- First, we initialize the sound engine. The init() function can optionally takes one argument, the device name. You can retrieve the list of devices, using this static function :

QStringList devicesList().

- Then, we create a KALsource. KALSource can be used for playing small sounds(shoot, scream, tic, walk, etc). It will load the entire file inside a buffer, so be careful if you try to play a big file using it.

If you want to try playing something else than the default "Hello World", you can download this short simple : [ocean.wav] and replace the sound object definition by:

KALSource *sound =new KALSource("ocean.wav");

You can only use it to play wav file at the moment, but we hope to bring ogg support soon.
For playing music, please wait until KALStream tutorial is up.

- The sound can now be played by simply calling play(). This function is asynchronous, meaning your program doesn't have to wait until the sound has finished playing to continue.

- Then, to know when the sound has ended, we create a loop using status() which returns ever AL_PLAYING or AL_STOPED.

- Inside the loop, we print the time since the sound started playing using elapsedTime(). It returns an ALfloat with the elapsed time expressed in seconds.

- Finally, we have to clear the KALSource buffer by deleting the KALSource pointer and close the device by calling shutdown().